Rapid processing is important to a light-sensitive material for prints among a variety of light-sensitive materials. Particularly rapid processing is important to such a product as a light-sensitive material for color prints. That product is used in a market in which there is strong demand for mass production of color prints in a short period of time. Developing time is reduced remarkably by developing a light-sensitive material that contains a silver halide emulsion having a high content of silver chloride. Such rapid processing technology has become popular in the market.
Recently, users can easily obtain prints in a variety of large sizes, such as panorama size and highvision size, in response to user needs. Accordingly, it is still further need to develop new technology for increasing the sensitivity of the light-sensitive material in order to avoid deterioration of the productivity of prints even when the light-sensitive material is exposed to light for such large-size prints.
As an effective method of obtaining high sensitivity, it has been known to use, for a light-sensitive material, a silver halide emulsion that is subjected to chemical sensitization with gold, selenium or tellurium. However, such a light-sensitive material, which contains a silver halide emulsion subjected to chemical sensitization, has the drawback of reduced sensitivity upon exposure to light under high humidity.
To incorporate a metal ion, such as iron and iridium, in a silver halide emulsion, as described in JP-A (JP-A means unexamined published Japanese Patent Application) No. 156452/1991, is effective. However it does not satisfactorily improve the reduction of sensitivity upon exposure to light under high humidity. Extensive investigation was carried out, concentrating on the technical point that the above-mentioned problem of reduced sensitivity might have been caused by a dye that is used for improving sharpness and the like. As a result, some improvement was observed by incorporating, in a light-sensitive material, a finely divided powder compound (as a dye) that is substantially water insoluble at a pH of at least 6 or less and substantially water soluble at a pH of at least 8 or more, as described in JP-A No. 308244/1990. However, the result was not satisfactory with respect to a remaining color due to a residual dye after a rapid processing.
Under such the circumstances, there has been a need to develop a dye that provides a little coloring after rapid processing and that minimizes the reduction of sensitivity upon exposure to light under high humidity when a silver halide emulsion chemically sensitized with gold, selenium or tellurium is used.